The participation of transgender or transsexual individuals in competitive sports is a controversial issue. Opposition to transgender or transsexual individuals competing in sporting events generally focuses on hormonal factors (such as higher testosterone levels among trans women), the socialisation of young men and women, and physiological factors such as height and weight. Insisting trans athletes compete against athletes of the same biological sex, sex verification testing, and access regulations have been used with the aim of ensuring fair competition.

Historically sport has been seen as a male domain.[1] The masculine perception of sport was first moderated with the rise of women's sports and further challenged with the gradual acceptance of gay sportsmen.[1] A third departure from this traditional view came from trans-athletes, who did not fit into the culturally accepted binary gender definition of male and female.[1]

The USTA and WTA introduced the Barr Body test, which identifies a person's sex chromosomes. Richards refused to take the test and was banned from the US Open.[2] She filed a lawsuit in 1977 claiming that her civil rights were violated. The judge agreed that the Barr body test as the sole determinant of sex was "grossly unfair" and ruled Richards legally female.[4] She competed in the 1977 Open, lost in the first round and retired four years later.[2] At the time the ruling in Richards case did not lead to major changes outside of tennis.[4]

In 2003, a committee convened by the International Olympic Committee (IOC) Medical Commission drew up new guidelines for participation of athletes who had undergone sex reassignment. The report listed three conditions for participation. First, athletes must have undergone sex reassignment surgery, including changes in the external genitalia and gonadectomy. Second, athletes must show legal recognition of their gender. Third, athletes must have undergone hormone therapy for an appropriate time before participation, with two years being the suggested time.[5]

It was not until 2004 that the IOC allowed transsexual athletes to participate in the Olympic Games.[6]

In 2015, the IOC modified these guidelines in recognition that legal recognition of gender could be difficult in countries where gender transition is not legal, and also that requiring surgery in otherwise healthy individuals "may be inconsistent with developing legislation and notions of human rights".[7][8] The new guidelines require only that trans woman athletes declare their gender and not change that assertion for four years, and demonstrate a testosterone level of less than 10 nanomoles/liter for at least one year prior to competition and throughout the period of eligibility. Athletes who transitioned from female to male were allowed to compete without restriction. These guidelines were in effect for the 2016 Rio Olympics, although no openly transgender athletes competed.[9]

In 2017 Mack Beggs, a teenager from Texas that was transitioning from female to male, was forced to wrestle in the girls state championship despite wanting to wrestle against boys. This was due to state sport regulations requiring athletes to compete alongside athletes of their birth gender. Some opponents say the testosterone prescribed as part of his transition gives him an unfair advantage and made it unsafe for the other wrestlers.[10]

At the heart of this controversy are concerns that transgender women would outperform cisgender women due to their more masculine body structure, socialisation as males and higher testosterone levels. The intense scrutiny of transgender athletes has focused on trans women because it is generally assumed that transitioning for transmasculine individuals would not confer a competitive advantage.[11]

Sports organizations have sought a test for sex verification to ensure fairness across all sports. This began in the 1940s with "femininity certificates" provided by a physician. In the 1960s, visual genital inspections were used to confirm gender, followed by chromosomal analysis to ensure that all athletes had an XX or XY chromosomal makeup. These tests were all designed to ensure that athletes were only allowed to compete as their sex, but mostly resulted in the exclusion of intersex athletes.[12]

More recently,[when?] testosterone levels have become the focus and, at the same time, new guidelines have been sought that would allow successfully-transitioned athletes to compete.[7]

People who oppose transgender women competing in women's sports say that they are given an unfair advantage over cisgender women due to their testosterone levels, and different muscle and fat distribution. Testosterone regulates many different functions in the body, including the maintenance of bone and muscle mass.[13] It is also argued that athletes who transition to a woman after puberty will have a greater muscle to fat ratio compared to female athletes.[14]

However, the use of estrogen supplements and testosterone blockers (or physical castration via sex reassignment) cause a decrease in muscle mass, bone density, and oxygen-carrying red blood cells. This leads to a decrease in strength, speed, and endurance.[15] According to Joanna Harper, a competitive runner, scientist, and transgender woman, every athlete has advantages and disadvantages. The greater height that a transgender woman may have gained before transitioning may be an advantage on the basketball court but it is likely to be disadvantageous to a gymnast.[16] Eric Vilain, a professor of human genetics at UCLA and a consultant to the IOC medical commission, stated: "There is 10 to 12% difference between male and female athletic performance. We need to categorize with criteria that are relevant to performance. It is a very difficult situation with no easy solution."[17]

States vary widely on participation of transgender children in sports and which locker room those students should use. Advocates in favor of allowing transgender children to participate in sports based on their preferred gender point out the known benefits of participating in sports and the psychological well-being of the transgender children.[18] Opponents emphasize the same issues of an unfair advantage of larger size and strength in trans women, plus the safety of cisgender children, both in competition and in the locker room.[19]

1.
Bissu
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The Bugis people are the most numerous of the three major ethnic groups of South Sulawesi, Indonesia. In contrast to the system of Western society, Bugis society recognises five genders, makkunrai, oroané, bissu, calabai. Makkunrai and oroané are comparable to women and men, respectively. Calalai and calabai approximately compare with trans men and trans women, bissu is one of the five genders of the Bugis, an Indonesian ethnic group. There are divergent theories regarding the origins and meaning of gender transcendent. To be considered bissu, all aspects of gender must be combined to form a whole and this can include those who are born intersex. However, being bissu does not necessarily mean one does not possess only fully functioning male or female sexual organs, the role of the bissu exist in Bugis society because it is a cultural belief that all five genders must harmoniously coexist. The advice of bissu is typically sought when a particular approval from the powers of the world is required. This may, for example, be the situation when a Bugis person is departing Sulawesi for the Hajj, in that situation the bissu will permit an excellent djinn to seize them and to proceed as an emissary of the batin. In this exceptional case, it means that the spirit and the Bissus powers should not be measured as in any way autonomous from Allah’s power, because he is the only one who is to be venerated. In daily social life, the bissu, along with the calabai, according to the Bugis gender system, a calabai is a false woman. Therefore, these people are assigned male at birth but take on the role of a heterosexual female. The fashions and gender expression of Calabai individuals are distinctly feminine, if there is to be a wedding in Bugis society, more often than not calabai will be involved in the organization. When a wedding date has been agreed upon, the family will approach a calabai, rarely did I attend a village wedding with less than a thousand guests. On the day, some remain in the kitchen preparing food while others form part of the reception. A calalai is a person who is assigned female at birth, calalai dress and present as men, hold masculine jobs, and typically live with female partners to adopt children. Gender Diversity in Indonesia, Sexuality, Islam and Queer Selves, the Bugis (The Peoples of South-East Asia and the Pacific. Gender binary Third gender Five Genders, skinner, Craig, ed. Soft Minded Men, South-East Asian Gender Crossing

2.
Calabai
–
The Bugis people are the most numerous of the three major ethnic groups of South Sulawesi, Indonesia. In contrast to the system of Western society, Bugis society recognises five genders, makkunrai, oroané, bissu, calabai. Makkunrai and oroané are comparable to women and men, respectively. Calalai and calabai approximately compare with trans men and trans women, bissu is one of the five genders of the Bugis, an Indonesian ethnic group. There are divergent theories regarding the origins and meaning of gender transcendent. To be considered bissu, all aspects of gender must be combined to form a whole and this can include those who are born intersex. However, being bissu does not necessarily mean one does not possess only fully functioning male or female sexual organs, the role of the bissu exist in Bugis society because it is a cultural belief that all five genders must harmoniously coexist. The advice of bissu is typically sought when a particular approval from the powers of the world is required. This may, for example, be the situation when a Bugis person is departing Sulawesi for the Hajj, in that situation the bissu will permit an excellent djinn to seize them and to proceed as an emissary of the batin. In this exceptional case, it means that the spirit and the Bissus powers should not be measured as in any way autonomous from Allah’s power, because he is the only one who is to be venerated. In daily social life, the bissu, along with the calabai, according to the Bugis gender system, a calabai is a false woman. Therefore, these people are assigned male at birth but take on the role of a heterosexual female. The fashions and gender expression of Calabai individuals are distinctly feminine, if there is to be a wedding in Bugis society, more often than not calabai will be involved in the organization. When a wedding date has been agreed upon, the family will approach a calabai, rarely did I attend a village wedding with less than a thousand guests. On the day, some remain in the kitchen preparing food while others form part of the reception. A calalai is a person who is assigned female at birth, calalai dress and present as men, hold masculine jobs, and typically live with female partners to adopt children. Gender Diversity in Indonesia, Sexuality, Islam and Queer Selves, the Bugis (The Peoples of South-East Asia and the Pacific. Gender binary Third gender Five Genders, skinner, Craig, ed. Soft Minded Men, South-East Asian Gender Crossing